Sharpening the boundaries between flux landscape and swampland by tadpole charge

Abstract

We investigate the vacuum structure of four-dimensional effective theory arising from Type IIB flux compactifications on a mirror of the rigid Calabi-Yau threefold, corresponding to a T-dual of the DeWolfe-Giryavets-Kachru-Taylor model in Type IIA flux compactifications. By analyzing the vacuum structure of this interesting corner of string landscape, it turns out that there exist perturbatively unstable de Sitter (dS) vacua in addition to supersymmetric and non-supersymmetric anti-de Sitter vacua. On the other hand, the stable dS vacua appearing in the low-energy effective action violate the tadpole cancellation condition, indicating a strong correlation between the existence of dS vacua and the flux-induced D3-brane charge (tadpole charge). We also find analytically that the tadpole charge constrained by the tadpole cancellation condition emerges in the scalar potential in a nontrivial way. Thus, the tadpole charge would restrict the existence of stable dS vacua, and this fact underlies the statement of the dS conjecture. Furthermore, our analytical and numerical results exhibit that distributions of $$ \mathcal{O}(1) $$ O 1 parameters in expressions of several swampland conjectures peak at specific values.

Scale-separated AdS$_4$ vacua of IIA orientifolds and M-theory

“…n . In deriving the above equations, we used our assumption that the first-order coefficients w (1) , T (1) and g (1) mn only depend on the coordinates y 2 , y 4 of the largest 18 Recall from Section 3.1 that…”

“…Moreover, the DGKT solutions are part of a larger class of vacua for which the CY condition is relaxed to an SU(3)-structure condition [16]. Whether these vacua are scale-separated is case-dependent and can be rather subtle [17] (see also [18] for a recent related study). Finally, scale-separated AdS solutions are claimed to exist in IIB supergravity on SU(2)-structure geometries with intersecting O5/O7 planes [19,20].…”

A new de Sitter solution with a weakly warped deformed conifold

“…The final vevs and mass hierarchies are not very different in the two regimes, being distinguished in our examples mainly by the vev of the conifold modulus, |z|, which is larger in the new regime, and the vev of the volume modulus, c, which ends up somewhat smaller. In the end, the tadpole numbers from the throat fluxes are M K ∼ O(100), similar to the LVS solution [18], and there also remains the issue of tadpole contributions from bulk fluxes [16,54,55]. In fact, the parameter space where we have found the new dS solutions have somewhat large values O(10 2 − 10 3 ) for W 0 , from the heavy bulk moduli, and for A, from the leading non-perturbative term to stabilise the Swiss Cheese moduli.…”

Type IIB flux compactifications with $h^{1,1}=0$

“…In this work we revisit and expand the results of [16][17][18]. We find new AdS, Minkowski and dS solutions and discuss them in the context of the swampland program.…”